This invention relates particularly to packaging for consumer goods which are pourable from a paperboard container through a pour spout located adjacent the top end of the container. Products such as milk and juices are commonly packaged in such prior art containers. Certain consumer products, such as, edible oils, laundry detergent or lubrication oils may not be packaged in prior art containers due to their tendency to leak through the bottom closure employed in prior art paperboard containers.
The packages of the present invention relate to, and are described herein with reference to, the well-known gable top container, but other containers of generally rectangular cross-section are encompassed within certain aspects of the present invention. These containers are commonly formed from a laminate, such as paperboard onto whose opposite surfaces a layer of heat sealable polymeric material has been extruded. Thus, in the present invention, both outer surfaces of the container include a heat sealable polymeric coating.
Existing production facilities for gable top containers commonly include an assembly line type production facility. In this assembly line a side-seamed container blank which is initially folded flat is fed into the assembly line. This blank is initially expanded into an open-ended tubular configuration and thereafter fitted over one of a plurality of mandrels which extend radially from a central drive shaft. Through control of the drive shaft, these mandrels, with their respective blanks, are indexed between various container-forming stations to ultimately define a container having a closed bottom end. This closed-end container is passed from its mandrel onto a conveyor which carries the container to and through a filling station and a top closure station. The functions of closing the top and bottom ends of a gable top container require that the container blank be oriented such that as it is passed through the machinery, its fold lines are properly aligned with the folding equipment of the assembly line. Specifically, in the prior art gable top container assembly line, the uppermost fin of the gable top must be oriented with the direction of movement of the container through the assembly line. Further, the prior art designs for the bottom closure of the container require that specific panels, tabs or flaps provided on the bottom ends of the side panels of the container be folded only in accordance with a single sequence. In these bottom closures, the folding sequence had a xe2x80x9chandnessxe2x80x9d, that is, the bottom closure forming equipment requires that the container be aligned in only one acceptable attitude or else the bottom closure can not be effected. Thus, in the prior art container assembly lines, the orientation of the top closure equipment and the orientation of the bottom closure equipment must be coordinated to accommodate each other.
Of recent, gable top containers have been provided with a pour spout affixed to one of the inclined top side panels of the container in flow communication with a through-opening which is pre-cut in one of the top panels of the container. The prior art assembly line equipment has been retrofitted with equipment suitable for affixing of the pour spout to the container by installing the necessary equipment within the existing assembly line downstream of the formation of the closed bottom of the container and the container filling station. The known equipment for affixing a pour spout to a container requires that the pre-cut hole for the pour spout be oriented on that side of the container which faces laterally outwardly of the direction of movement of the container along the assembly line. This requirement is dictated by reason of the physical space required to position to the pour spout-affixation equipment such that there is access to the through-opening in the top end of the container for placement of the pour spout and its affixation to the container.
In the prior art, efforts to increase the productivity of the machines employed to form and fill containers having included the concept of combining at least a second assembly line in generally parallel relationship to a first assembly line and using common housing, sterilization systems, drive systems, etc. for the two lines. These prior multiple assembly lines could employ identical container-forming and filling equipment on each line because the orientation of the container being fed into and through each of the lines could be the same for each line.
With the advent of pour spouts, because the pour spout affixation equipment must be positioned laterally outboard of each of the assembly lines of a dual assembly line arrangement, the container blanks being fed into the assembly lines must be oriented as mirror images of one another so that the through-opening for the pour spout of each container blank is facing laterally outwardly of the direction of movement of the blanks along each of the assembly lines and therefore accessible to the pour spout affixation equipment associated with a respective line. This required orientation of the container blanks requires minimal alteration of the equipment of each assembly line. First, it dictates that the mandrel carousel of each assembly line of a dual assembly line arrangement be substantially a mirror image of the mandrel carousel of the other of the assembly lines. When changing a prior art mandrel carousel from xe2x80x9cleft-handnessxe2x80x9d to a xe2x80x9cright handnessxe2x80x9d, that is, when converting two mandrel carousels of the prior art into mirror images of one another, one must make changes in one of the carousels including (a) rotating the oven heater head in the first forming (and heating) station by 180 degrees; and (b) rotating the pressure pad employed in the sealing of the panels of a bottom closure by 180 degrees. Moreover, such a change requires an inventorying of two differing sets of replacement parts for the mandrel carousels.
It is therefore an object of the present invention to provide a universal bottom closure design for use in the forming and filling of gable top containers having pour spouts.
It is another object to provide a method and apparatus for forming and filling of gable top containers having pour spouts.
It is another object to provide a container blank for use in the forming of a gable top container which includes a pour spout.
It is another object to provide a pressure pad for use on the distal end of a carousel mandrel in the forming of the bottom closure of a gable top container which includes a pour spout.
In accordance with one aspect of the present invention, there is provided a method for the forming and filling of pour spout-containing containers of the gable top variety employing multiple assembly lines having various of the components thereof common to all the lines, such as the drive, housing, sterilization system, etc. Apparatus for carrying out the method is disclosed, as is a novel container blank which is universal with respect to its acceptability on either of the multiple assembly lines, especially with respect to its bottom closure design.